The present invention relates to vacuum cleaners, more particularly to liquid bath vacuum cleaners. In the past, liquid bath vacuum cleaners have mixed motor cooling air and cleaning air during the cleaning process. Examples of prior art are U.S. Pat. Nos. 2,886,127, 2,945,553, and 2,954,095, illustrating different embodiments of liquid bath vacuum cleaners. All embodiments show the mixing of cooling air and cleaning air during the cleaning process. Applicant has determined that the cooling of the drive motor from the vacuum cleaner can be improved with separation of the cooling air from the cleaning air. Thus, a need in the field has existed to separate the cleaning air stream from the motor cooling air stream to alleviate the mixing of these air streams and improve the cooling of the drive motor along with increasing the life of the motor by this increased cooling efficiency.
Accordingly, it is a primary object of the present invention to separate the cleaning air from the cooling motor air to improve the cooling efficiency of the vacuum cleaner cooling the drive motor. Another object of the present invention is improved sealing between the cleaning air and cooling air portions of the vacuum cleaner to maintain driven cooling air.
To achieve the foregoing objects, the present invention provides a liquid bath vacuum cleaner which generally comprises a water pan, a main housing assembly, cap assembly, motor assembly, a fan assembly, means for separating the suction air from the cooling air, and a separator. The water pan assembly has a socket, acting as a suction end, for connection to a conventional cleaning hose. Cleaning air including dirt and dust particles enters the water pan assembly which contains a predetermined amount of liquid and the dirt and dust particles are separated from the air. The dust and dirt particles remain in the liquid and the cleansed air passed through the separator, through the fan assembly, and into the main housing cavity, and exits into the ambient air through a plurality of apertures in the main housing assembly wall.
In an alternate embodiment a baffle plate may be positioned between the water pan assembly and the main housing assembly. The baffle plate encloses the main housing assembly from the pan assembly thus preventing dust particles from collecting on the pan assembly. Also, the baffle plate adds support to the main housing assembly along with providing improved noise dampening characteristics.
The separate motor cooling air is drawn into the cap assembly by the motor fan. The cooling air circulates around the motor assembly to cool the motor assembly, passes through a gap in the inner canister into the cap assembly cavity, and exits into the ambient air through a plurality of apertures in the cap assembly wall. Thus, the cooling air stream and cleaning air stream are separated to eliminate the possibility of combining contaminants with the air cooling the motor.
Additional advantages and features of the present invention will be apparent from the subsequent description and the appended claims taken in conjunction with the accompanying drawings.